-
A New Approach to Estimate Hansen Solubility Parameters Using Maple Software
Ra'id Khider Salman,
Jassim Mohammed Salih
Issue:
Volume 5, Issue 5, September 2016
Pages:
183-187
Received:
20 July 2016
Accepted:
30 July 2016
Published:
17 August 2016
Abstract: This paper represents the use of Maple software capabilities in the analyses of the polymer- solvent interactions. It illustrates the advantages of using Maple to estimate Hansen solubility parameters and to predict the polymer-solvent miscibility. The study focuses on the polymers and solvents that are employed in the polymer gel electrolytes. The acquired data showed high consistency and flexibility in calculations and estimations processes, especially in regarding with Hansen sphere plotting and relative energy distance calculations.
Abstract: This paper represents the use of Maple software capabilities in the analyses of the polymer- solvent interactions. It illustrates the advantages of using Maple to estimate Hansen solubility parameters and to predict the polymer-solvent miscibility. The study focuses on the polymers and solvents that are employed in the polymer gel electrolytes. The...
Show More
-
Synthesis and Characterization of Electrodeposited Tin Disulphide (SnS2) Thin Films for Photovoltaic Application
A. Ramoni Lasisi,
Olayinka. A. Babalola,
Bidini. A. Taleatu,
Aderemi. B. Alabi,
Ezekiel Omotoso,
Taye Akomolafe
Issue:
Volume 5, Issue 5, September 2016
Pages:
188-193
Received:
8 August 2016
Accepted:
16 August 2016
Published:
5 September 2016
Abstract: This paper reports the study on structural, morphology and optical properties of electrodeposited tin disulphide (SnS2) thin films. The thin films were synthesise from SnSO4, Na2S2O3 and H2SO4 and were deposited on Indium tin oxide coated glass slide. The films were characterized using X-Ray Diffractometer (XRD), SEM-EDS, AFM and UV-Visible spectrophotometer in the visible region. The EDS shows the presence of Sn and S. The SEM result reveals that, the film is continuous, pin-hole and crack free. The grain size of 0.31 µm was calculated for the film. The XRD result reveals the films to be crystalized with hexagonal structure and lattice parameters a=b= 3.645 Å and c = 11.802 Å. The crystal size was estimated to be 52.3 nm and inter-planar spacing was estimated to be 0.5 nm. The AFM confirms the film to be continuous, pin-hole and crack free. The average growth height of the film is estimated to be 90.5 nm. The transmittance of the films is about 78% and is a direct band gap material with band gap energy of 2.8 eV. Thus, the film can be used as a buffer layer in thin film solar cells and other optoelectronic devices.
Abstract: This paper reports the study on structural, morphology and optical properties of electrodeposited tin disulphide (SnS2) thin films. The thin films were synthesise from SnSO4, Na2S2O3 and H2SO4 and were deposited on Indium tin oxide coated glass slide. The films were characterized using X-Ray Diffractometer (XRD), SEM-EDS, AFM and UV-Visible spectro...
Show More
-
Matrix Shear-Lag Parameter in a Shape Memory Alloy-Actuator-Reinforced Silicon Elastomer
Issue:
Volume 5, Issue 5, September 2016
Pages:
194-201
Received:
11 August 2016
Accepted:
22 August 2016
Published:
9 September 2016
Abstract: The excellent qualities possessed by silicon elastomer when used in designing flexible parts of mechanical systems, make it imperative that we analyze its deformations and distributed axial forces in a matrix of shape memory alloy (SMA) fibers designed as possible appendages for gripping robots. The essence of these analyses is to determine the shear-lag parameter which has influence on the axial distributed forces proposed as a gauge for testing the structure in a high yield, high force and high strain mechanical environment. The insertion of SMA fibers in flexible rods cast using silicon elastomer results in the deformation of the host medium once shape recovery of the fiber occurs. This paper aims to analyze the mechanics of the said shape recovery in a modeled silicon elastomer rod with a single off-axis reinforced SMA actuator. The compressive force distribution mechanism and the bending moment caused by phase transformation in the design are determined using an approximate analytical model. The deformations on the structure proposed as an appendage on gripping robots were further analyzed by determining their equations of equilibrium, force factors and their comparative shear-lag models to be able to estimate the force distribution on the structure.
Abstract: The excellent qualities possessed by silicon elastomer when used in designing flexible parts of mechanical systems, make it imperative that we analyze its deformations and distributed axial forces in a matrix of shape memory alloy (SMA) fibers designed as possible appendages for gripping robots. The essence of these analyses is to determine the she...
Show More
-
The Structural, Elastic, Electronic and Optical Properties of Cubic Perovskite SrVO3 Compound: An Ab Initio Study
Md. Lokman Ali,
Md. Zahidur Rahaman
Issue:
Volume 5, Issue 5, September 2016
Pages:
202-206
Received:
8 May 2016
Accepted:
20 May 2016
Published:
12 September 2016
Abstract: The structural, elastic, electronic and optical properties of cubic SrVO3 perovskite have been investigated using the first principles pseudo-potential plane-wave (PP-PW) method based on the density functional theory (DFT), within the generalized gradient approximation (GGA). The calculated lattice parameters are in good agreement with the previous experimental and theoretical results. Using the energy-strain method, we obtained three independent elastic constants (C 11, C 12 and C 44) and various elasticity parameters such as bulk modulus, Shear modulus, Young’s modulus, B/G, Poisson’s ratio and anisotropy factor. Our calculated results of elastic constants satisfy the structural stability criterion and the ductile/brittle of SrVO 3 is predicted by Pugh’s criterion. The electronic band structure reveals metallic conductivity. Finally, the optical properties (reflectivity, dielectric function, refractive index, absorption spectrum, conductivity and energy loss spectrum) have been calculated and discussed.
Abstract: The structural, elastic, electronic and optical properties of cubic SrVO3 perovskite have been investigated using the first principles pseudo-potential plane-wave (PP-PW) method based on the density functional theory (DFT), within the generalized gradient approximation (GGA). The calculated lattice parameters are in good agreement with the previous...
Show More
-
Influence of pH Preparation on the Photo-Response of Electrodeposited Titanium Dioxide (TiO2) Thin Films
Toto Mabiala Masiala,
Albert Kazadi Mukenga Bantu,
Gracian Ekoko Bakambo,
Jérémie Muswema Lunguya,
Joseph Lobo Kanza Kanza,
Omer Mvele Muamba
Issue:
Volume 5, Issue 5, September 2016
Pages:
207-213
Received:
12 August 2016
Accepted:
30 August 2016
Published:
29 September 2016
Abstract: The anodic oxidation method has been used to prepare thin films of titanium dioxide (TiO2) in acid and alkaline electrolytes. The influence of pH on the structure, the morphology and the photo response of the deposited TiO2 has been evaluated by measuring the current density. The experimental results showed that the photo current response was pH dependent. The acid electrolytes being the best medium in producing stable oxide films with good adhesion to titanium metal substrate and good charging rate and current density.
Abstract: The anodic oxidation method has been used to prepare thin films of titanium dioxide (TiO2) in acid and alkaline electrolytes. The influence of pH on the structure, the morphology and the photo response of the deposited TiO2 has been evaluated by measuring the current density. The experimental results showed that the photo current response was pH de...
Show More
-
Silver Nanoparticles as Artificial Antennas for Enhanced Light-Harvesting and Charge Transfer in Dye-Sensitized Solar Cells
Eli Danladi,
Philibus Musa Gyuk,
Muhammad Sani Ahmad,
Isah Baba,
Sunday Habila Sarki
Issue:
Volume 5, Issue 5, September 2016
Pages:
214-221
Received:
14 September 2016
Accepted:
22 September 2016
Published:
11 October 2016
Abstract: We present an investigation on introducing core-shell Ag@SiO2 nanoparticles (NPs) into dye-sensitized solar cells. Ag@SiO2 present the chemical stability to iodide/triiodide electrolyte, and help to localize most of dye molecules around plasmonic silver nanoparticles (AgNPs), hence increasing the optical absorption consequently the overall conversion efficiency of the device. Deployment of the silver-modified assembly as a photo anode in dye-sensitized solar cells leads to solar-to-electrical energy conversion with an overall efficiency of 0.0088% for Ag-TiO2 photo anode and 0.0176% for Ag@SiO2-TiO2 photo anode. This represents a 100.7% improvement over the performance of otherwise identical solar cell lacking corrosion-protected silver nanoparticles. The improvement is manifested chiefly as an increase in photocurrent density due to enhanced light harvesting by the AgNPs. The results revealed that, the performance of DSSCs could be well improved through enhancing the light absorption by local surface plasmon (LSP) effect from Ag@SiO2 NPs by electronically and chemically protecting the metal from recombination and corrosion. The mechanism of getting the best utilization efficiency of LSP enhanced optical field is also investigated.
Abstract: We present an investigation on introducing core-shell Ag@SiO2 nanoparticles (NPs) into dye-sensitized solar cells. Ag@SiO2 present the chemical stability to iodide/triiodide electrolyte, and help to localize most of dye molecules around plasmonic silver nanoparticles (AgNPs), hence increasing the optical absorption consequently the overall conversi...
Show More
-
Surface Valence States of Mn Ions and Magnetic Properties of La0.67Sr0.33MnO3 Films
Ruikun Pan,
Yang Li,
Fan Fang,
Wanqiang Cao
Issue:
Volume 5, Issue 5, September 2016
Pages:
222-227
Received:
13 October 2016
Published:
13 October 2016
Abstract: La0.67Sr0.33MnO3 (LSMO) films were prepared on SrTiO3 single-crystal substrates by the pulsed laser deposition method. X-ray photoelectron spectra (XPS) were measured for the LSMO films as-prepared, annealed in oxygen and in vacuum, respectively. Multiple peaks fitting for Mn 2p3/2 XPS spectra shows that Mn2+ appears and the ratio of Mn3+/Mn4+ increases on the surface of LSMO film annealed in vacuum comparing with the as-prepared film, though the saturation magnetization (Ms) changes little. Mn6+ and Mn7+ can be detected while Mn4+ decreases much on the surface of LSMO film annealed in oxygen. The change of Mn3+/Mn4+ results in the obviously reduce of Ms. O1s spectra show the gradual changes of Mn-O, Sr-O and La-O. Analysis indicates that Mn2+ forms at the surface defects of LSMO films. Annealing in vacuum hardly affects the magnetic property of LSMO films. But annealing in oxygen greatly changes the valence states of Mn, which weakens the magnetic property of LSMO films.
Abstract: La0.67Sr0.33MnO3 (LSMO) films were prepared on SrTiO3 single-crystal substrates by the pulsed laser deposition method. X-ray photoelectron spectra (XPS) were measured for the LSMO films as-prepared, annealed in oxygen and in vacuum, respectively. Multiple peaks fitting for Mn 2p3/2 XPS spectra shows that Mn2+ appears and the ratio of Mn3+/Mn4+ incr...
Show More
-
The Effect of Self-Diffusion on the Zn Diffusion in III-V Compound Semiconductors
Liangliang Tang,
Chang Xu,
Zhuming Liu
Issue:
Volume 5, Issue 5, September 2016
Pages:
228-234
Received:
13 October 2016
Published:
13 October 2016
Abstract: Zn diffusion in III-V compound semiconductors are commonly processed under group V-atoms rich conditions because the vapor pressure of group V-atoms is relatively high. In this paper, we found that group V-atoms in the diffusion sources would not change the shaped of Zn profiles, while the Zn diffusion would change dramatically under group III-atoms rich conditions. The Zn diffusions were investigated in typical III-V semiconductors: GaAs, GaSb and InAs. We found that under group V-atoms rich or pure Zn conditions, the double-hump Zn profiles would be formed in all materials except In As. While under group III-atoms rich conditions, single-hump Zn profiles would be formed in all materials. Detailed diffusion models were established to explain the Zn diffusion process; the surface self-diffusion of matrix atoms is the origin of the abnormal Zn diffusion phenomenon.
Abstract: Zn diffusion in III-V compound semiconductors are commonly processed under group V-atoms rich conditions because the vapor pressure of group V-atoms is relatively high. In this paper, we found that group V-atoms in the diffusion sources would not change the shaped of Zn profiles, while the Zn diffusion would change dramatically under group III-atom...
Show More
